The use of heteroatom-substituted oxyallyl cations in (4+3) cycloadditions has had a tremendous impact on the development of cycloaddition chemistry. Extensive efforts have been exerted toward investigating the effect of oxygen, sulfur, and halogen substituents on the reactivity of oxyallyl cations. ...
Catalytic cycloaddition took place in ethanol as the most efficient solvent system. The results could be explained by the much better solubility of the organic molecules and the much better dispersion of the catalyst in the EtOH solvent. Table 1 Optimized conditions to synthesize of 3,4-dihydro...
Phosphine-Catalyzed [3 + 2] Cycloaddition of 4,4-Dicyano-2-methylenebut-3-enoates with Benzyl Buta-2,3-dienoate and Penta-3,4-dien-2-one 4,4-Dicyano-2-methylenebut-3-enoates are employed in the phosphine-catalyzed [3 + 2] cycloaddition with allenoates for the first time, affording re...
tandem cycloadditionsSummary This chapter focuses on tandem cycloadditions that are initiated by a [4 + 2] cycloaddition step that generates a 1,3-dipole or a precursor to a 1,3-dipole, which then engages in a [3 + 2] cycloaddition. Compared to the cycloadditions of nitroalkenes, tandem ...
applications (Fig. 5). CD polymer synthesis methods mainly include reversible addition–fragmentation transfer polymerization, ring opening polymerization, atom transfer radical polymerization, Cu(I)-catalyzedazide–alkyne cycloaddition reaction, amidation and thiol-bromo click reaction methods (Yao et al.,...
Interactive 3D chemistry animations and models of the spinel structure of LiMn2O4, lithium ion diffusion is 3 dimensional, so it can also diffuse in 2 dimensional planes.
Intramolecular [4+2] and [3+2] Cycloadditions in Organic Synthesis Numerous examples of intramolecular cycloaddition of 1,3-dienes, nitrones, and azomethine imines attest the preparative value of this variant for regiosele... W Oppolzer - 《Angewandte Chemie International Edition》 被引量: 2062...
A novel benzopyrano[4,3-d]pyrimidine scaffold was generated via a three-component one-pot reaction from iodochromone, alkyne, and an amidine through a Sonogashira coupling, condensation, and cycloaddition. This combinatorial synthetic approach provides an efficient, easy construction of a diversified ...
N-Heterocyclic phosphenium cations: Syntheses and cycloaddition reactions A series of trifluoromethanesulfonate (OTf) salts ofN-heterocyclic phospheniums (NHP) bearing phenyl (1a),para-methoxyphenyl (1b), 2,6-diisopropylphenyl (1... CA Caputo,JT Price,MC Jennings,... - 《Dalton Transactions》...
Other examples of 3- and 5-(-D-ribofuranosyl)isoxazoles4 and their carbocyclic analogues5 have recently been demonstrated. General method of syntheses of the above heterocycles involves 1,3-dipolar cycloaddition of some olefinic or acetylenic dipolarophiles to sugar nitrile oxides, or the inverse ...